WATCH: Brad Pitt's foundation being sued for homes built in New Orleans.

A lawyer plans to sue actor Brad Pitt’s foundation over the degradation of homes built in an area of New Orleans that was among the hardest hit by Hurricane Katrina.

The lawsuit against Pitt’s Make It Right foundation, which built homes for New Orleans residents after Hurricane Katrina destroyed their homes in 2005, was brought on behalf of residents Lloyd Francis and Jennifer Decuir, who lawyer Ron Austin said have reported sicknesses, headaches, and infrastructural issues.

Enlisting award-winning architects, Pitt founded the venture in 2007, two years after Katrina devastated the city.

Construction began in 2008, working toward replacing the lost housing with 150 avant-garde dwellings that were storm-safe, solar-powered, highly insulated, and “green.”

The homes were available at an average price of US$150,000 to residents who received resettlement financing, government grants and donations from the foundation itself.

But 10 years and more than $26 million later, construction has halted at around 40 houses short of Pitt’s goal, and some homes are falling apart and residents have reported sagging porches, mildew on wood and leaky roofs.

“Essentially, Make It Right was making a lot of promises to come back and fix the homes that they initially sold these people and have failed to do so,” Austin said.

He added that the residents “were forced to file this lawsuit because the Make It Right Foundation built substandard homes that are deteriorating at a rapid pace while the homeowners are stuck with mortgages on properties that have diminished values.”

Francis and Decuir state in the document that they “were and are extremely grateful to Mr. Pitt for spearheading the rebuilding of the Lower Ninth Ward because their neighbourhood housed more than their homes. It housed their community.”

They also allege that Make It Right was aware of issues with the materials used to build homes by 2013 but “never provided homeowners with notice of these design and material defects” even with the residents paying for mortgages on the homes.

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The foundation in 2014 did spend an average of $12,000 on each of 39 homes to replace the deteriorating TimberSIL lumber, which was billed as environmentally friendly, weatherproof and durable.

Make It Right then sued TimberSIL for $500,000, but it’s unclear whether that dispute was settled.

A year later, Pitt expressed satisfaction with what had turned into a proper Crescent City neighbourhood.

“I get this swell of pride when I see this little oasis of colour and the solar panels,” Pitt told The Times-Picayune in 2015. “I drive into the neighbourhood and I see people on their porch, and I ask them how is their house treating them? And they say, ‘Good.’ And I say ‘What’s your utility bill?’ And they’ll throw something out like, ’24 bucks’ or something, and I feel fantastic.”

Earlier this summer, Make It Right made headlines in New Orleans again with the demolition of one of the houses. Having been unoccupied for years, the mouldy house demolished in June was described by The Times-Picayune as “a tattered loaf of rotting wood, fraying tarpaulin and ominous open doorways.”

Resident Constance Fowler made city hall aware of several building code violations, and The New Orleans Advocate reported that Make It Right paid for the demolition, citing a contract.

The foundation provided a written statement in April about the blighted house and other residential problems.

“Our homeowners’ well-being and privacy are some of our top priorities and we work closely with them to address their concerns,” the statement read. “Each situation is different and we are currently co-ordinating the necessary followup with the appropriate parties to address any areas of concern.”

The report didn’t indicate how many residents would join Austin’s lawsuit, and many residents quoted in news articles this year said that despite some problems, they were appreciative of the foundation’s work. Fowler herself told The Times-Picayune that without Make It Right, she might never have been able to afford a house.

Pitt’s New Orleans house-building charity also came under fire due to massive construction delays, shoddy homes and the exodus of several top-level executives in July 2016.

Residents said that the foundation’s director of innovations, Tim Duggan, left his position. Longtime CEO Tom Darden also left the foundation, along with at least four other board members.

“I think they have seven or nine board members and four of them are gone,” Urban Neighborhood Initiative executive director Dianne Cleaver told The Star.

Common Ground Relief executive director Thom Pepper had reported complaints from existing homeowners, who said that their homes needed to be rebuilt or substantially repaired in order to fix mistakes in construction.

Canadian contractor and builder Mike Holmes partnered with Pitt in 2008, after discovering that his trademarked phrase (“Make It Right”) was being used by Pitt.

“We heard of Brad Pitt’s intentions and I would never cause a fuss over anything that had to do with doing things the right way,” Holmes said at the time. “We sent them an e-mail saying ‘We just want you to know I own the trademark, and we want to talk to you about doing this together.’”

Holmes’s TV show, Holmes on Homes, shot a two-hour special about the building experience. It aired in January 2009.

Holmes’ association with Pitt’s foundation was limited to building one house in the neighbourhood for the two-hour special.

“Mike Holmes’ team built one house in the Lower Ninth Ward of New Orleans in the summer of 2008 which was verified as a LEED Platinum Home,” a statement from Holmes’ rep read. “It was Mike’s hope that the house his team built would become an example of the type of home-building the charity and the other building partners would replicate in the Lower Ninth. We have been in touch with the homeowner since and she continues to be happy with the house. We are saddened to hear that there are ongoing issues with some of the other homes. However, since our initial involvement in 2008, we have had no association with the Make It Right charity.”